In the current scenario, robotic snake have several useful applications in infrastructure monitoring, security and surveillance, repair and maintenance, under water exploration etc. For useful implementation of the robotic snake, it is necessary that the robotic snake exhibit different kinds of movements.
Various types of robotic snakes are existing in the prior art using different number of joint mechanisms to exhibit different motions. These joint mechanisms may exhibit one, two or three degrees of freedom (DOF) of motion. They are further classified into different types joint mechanism depending on the kind of joints used.
Existing 2 DOF joint mechanisms are further classified into various types—A, B, C and D depending on the kind of joints used. In an example, type A mechanism use a series of universal joints to produce 2 DOF motion. In another example, type B snake robots use a series of 1 DOF revolute joints that are oriented 90* with each other. The type C consists of joints that bend using oblique rotational axis to the roll axis. The 2 DOF joint mechanism having a rotational and a translational degree of freedom is referred to as a type D mechanism.
In another example existing 2 DOF joint mechanism use rotational degree of freedom and exhibits lateral undulations to move forward cannot exhibit a true rectilinear motion which is essential while moving in confined areas. There are a few joint mechanisms that use rotational as well as translational degree of freedom to achieve rectilinear motion along with other motions like turning. In one of the example, a robotic snake has 7 links and 8 joints (5 revolute and 3 prismatic) which are actuated by two servo motors produces rectilinear and turning The existing robotic snakes are complex and require several number of joints to exhibit one or two types of motion.
Various other robotic mechanism have been explained in the prior but there is a need to provide a robotic snake with lesser number of joints and 2 DOF joint mechanism which is able to exhibit three types of motion i.e. rectilinear, sidewinding and turning motion.